The present invention relates to drive devices for use with a beverage brewing apparatus. More specifically, the present invention envisions a multiple orientation drive device for use in driving a brewing component in a brew chamber of the beverage brewing apparatus.
A number of brewing devices are available which produce a brewed beverage using a substantially automated process. An example of an automatic beverage brewing apparatus is shown in U.S. Pat. No. 5,134,925 to Bunn et al. issued Aug. 4, 1992, incorporated herein by reference. A beverage brewing device as shown in Bunn et al. has a brew chamber which receives a charge of beverage brewing substance and infuses this substance with water to produce a brewed beverage therefrom. The brewed beverage is drained from the brew chamber and dispensed into an appropriate container. The brew chamber has a top assembly and a bottom assembly through which are formed a throat and a drain, respectively. A brewing component or piston extends into the brew chamber selectively shifting through the throat and the drain during a brewing cycle. The brewing component or piston is operated by a drive device attached thereto.
During a brew cycle, the piston is axially shifted downwardly by the drive device to receive a charge of brewing substance. The piston then shifts axially upwardly to close the throat and drain whereupon a quantity of water is dispensed to infuse the brewing substance and produce a brewed beverage. The brewed beverage is drained out of the brew chamber and dispensed into a collection container. Next, the piston is shifted upwardly to disengage a lower portion of the piston from the drain thereby draining the spent beverage brewing substance and any waste water out of the brew chamber. As shown in Bunn et al., the piston includes a flush water bore which extends therethrough to dispense water from a central area of the brew chamber. The piston is axially rotated and linearly shifted through the throat and drain to flush the inside surface of the brew chamber.
The drive device used in Bunn et al. employs a single drive assembly for both rotating and axially shifting the piston. A sensor is mounted in position relative to one of the rotating gears of the drive assembly to detect the movement of magnets mounted in the selected gear. Linear shifting is achieved by a threaded portion of the piston shaft being driven through a fixed, cooperatively threaded nut body. While the integrated rotary and linear drive device as shown in Bunn et al. is effective at driving the piston, there are applications where it is desirable to rotate the piston without linearly shifting it through the brew chamber and also linearly shifting the piston without rotating it in the chamber. As such, the device as shown in Bunn et al. cannot independently rotate nor linearly shift the piston.